A/B Testing: Also known as split testing or bucket testing, is a method of marketing testing by which a baseline control sample is compared to a variety of single-variable test samples in order to improve response rates. A classic direct mail tactic, this method has been recently adopted within the interactive space to test tactics such as banner ads, emails and landing pages.
adCenter: See Microsoft adCenter
AdWords: See Google AdWords
Affiliate Program: A marketing practice in which a business rewards one or more affiliates for each visitor or customer brought about by the affiliate’s own marketing efforts. Examples include rewards sites, where users are rewarded with cash or gifts, for the completion of an offer, and the referral of others to the site. The industry has four core players: the merchant (also known as ‘retailer’ or ‘brand’), the network, the publisher (also known as ‘the affiliate’), and the customer.
Algorithm: The formula which a search engine uses to determine the optimal order to present the search results to the user. Search algorithms are continually tweaked primarily to optimize the experience for the user, or give the closes approximation to what the user wanted to see when they entered the search term.
Article Marketing: A type of advertising in which businesses write short articles related to their respective industry. These articles are made available for distribution and publication in the marketplace. Each article has a bio box and byline (collectively known as the resource box) that include references and contact information for the author’s business. Well-written content articles released for free distribution have the potential to increase the business credibility within its market. Also it helps in attracting new clients. These articles are often syndicated by other websites, and published on multiple websites.
Attention Profile (APML): An XML-based format for expressing a person’s interests and dislikes. APML allows people to share their own personal attention profile in much the same way that OPML allows the exchange of reading lists between news readers. The idea behind APML is to compress all forms of attention data into a portable file format containing a description of the user’s rated interests.
Attribution: Also known as Campaign Attribution, it is the act of giving credit to the steps in the conversion process which contributed to the desired result.
Behavioral Targeting: Using information collected on an individual’s web-browsing behavior, such as the pages they have visited or the searches they have made, to select which advertisements to display to that individual. Practitioners believe this helps them deliver their online advertisements to the users who are most likely to be interested.
Bing Webmaster Center: A search service as part of Microsoft’s Bing search engine which allows webmasters to add their websites to the Bing index crawler. The service also offers tools for webmasters to troubleshoot the crawling and indexing of their website, sitemap creation, submission and ping tools, website statistics, consolidation of content submission, and new content and community resources.
Bounce Rate: Sometimes confused with exit rate, is an Internet marketing term used in web traffic analysis. It represents the percentage of visitors who enter the site and “bounce” (leave the site) rather than continue viewing other pages within the same site.
Blog: A blend of the term “web log” is a type of website or part of a website supposed to be updated with new content from time to time. Blogs are usually maintained by an individual with regular entries of commentary, descriptions of events, or other material such as graphics or video. Entries are commonly displayed in reverse-chronological order. Blog can also be used as a verb, meaning to maintain or add content to a blog.
Bucket Testing: See A/B Testing
Buzz Marketing: See Viral Marketing
Call to Action (CTA): Part of a clear marketing message, either in and online advertisement or on a webpage, which elicits the desired action from the user.
Canonicalization: URL canonicalization deals with web content that has more than one possible URL. Having multiple URLs for the same web content can cause problems for search engines – specifically in determining which URL should be shown in search results.
Click-through Rate (CTR): A way of measuring the success of an online advertising campaign. The click-through rate of an advertisement is defined as the number of clicks on an ad divided by the number of times the ad is shown (impressions), expressed as a percentage.
Cloaking: A search engine optimization (SEO) technique in which the content presented to the search engine spider is different from that presented to the user’s browser. This is done by delivering content based on the IP addresses or the User-Agent HTTP header of the user requesting the page.
Click Fraud: A type of Internet crime that occurs in pay per click online advertising when a person, automated script or computer program imitates a legitimate user of a web browser clicking on an ad, for the purpose of generating a charge per click without having actual interest in the target of the ad’s link.
Content Management System (CMS): A system providing a collection of procedures used to manage work flow in a collaborative environment. These procedures can be manual or computer-based.
Content Marketing: An umbrella term encompassing all marketing formats that involve the creation or sharing of content for the purpose of engaging current and potential consumer bases. Content marketing subscribes to the notion that delivering high-quality, relevant and valuable information to prospects and customers drives profitable consumer action. Content marketing has benefits in terms of retaining reader attention and improving brand loyalty.
Contextual Advertising: A form of targeted advertising for advertisements appearing on websites or other media, such as content displayed in mobile browsers. The advertisements themselves are selected and served by automated systems based on the content displayed to the user.
Conversion: Conversions are interpreted differently by individual marketers, advertisers, and content creators. To online retailers, for example, a successful conversion may constitute the sale of a product to a consumer whose interest in the item was initially sparked by clicking a banner advertisement. To content creators, however, a successful conversion may refer to a membership registration, newsletter subscription, software download, or other activity that occurs due to a subtle or direct request from the content creator for the visitor to take the action.
Conversion Funnel: A technical term used in e-commerce operations to describe the track a consumer takes through an Internet advertising or search system, navigating an e-commerce web site and finally converting to a sale.
Conversion Rate: The ratio of visitors who convert casual content views or website visits into desired actions based on subtle or direct requests from marketers, advertisers, and content creators.
Conversion Rate Optimization (CRO): The method of creating an experience for a website or landing page visitor with the goal of increasing the percentage of visitors which convert into customers.
Copywriting: The use of words and ideas to promote a person, business, opinion or idea.
Cost-per-Click (CPC): An Internet advertising model used to direct traffic to websites, where advertisers pay the publisher (typically a website owner) when the ad is clicked. With search engines, advertisers typically bid on keyword phrases relevant to their target market.
Cost-per-Thousand Impressions (CPM): A form of online advertising where the advertiser pays for every one-thousand times an ad is shown to a group of users.
Crawler/Spider/Robot: A computer program that browses the World Wide Web in a methodical, automated manner or in an orderly fashion. Other terms for Web crawlers are ants, automatic indexers, bots, Web spiders and Web robots. Many sites, in particular search engines, use spidering as a means of providing up-to-date data. Web crawlers are mainly used to create a copy of all the visited pages for later processing by a search engine that will index the downloaded pages to provide fast searches.
Directories: A web directory or link directory is a directory on the World Wide Web. It specializes in linking to other web sites and categorizing those links. A web directory is not a search engine and does not display lists of web pages based on keywords; instead, it lists web sites by category and subcategory.
Direct Traffic: A source of website traffic that comes from a user typing the sites URL directly in address bar, or coming back to the site through a bookmark in their web browser.
Display Advertising: A type of advertising that typically contains text (i.e., copy), logos, photographs or other images, location maps, and similar items. Display advertising appears on web pages in many forms, including web banners. Banner ad standards continue to evolve.
Electronic Commerce: Commonly known as e-commerce, eCommerce or e-comm, refers to the buying and selling of products or services over electronic systems such as the Internet and other computer networks.
Exit Rate: Sometimes confused with bounce rate, essentially represents the percentage of visitors to a site who actively click away to a different site from a specific page, after possibly having visited any other pages on the site. The visitors just exited on that specific page.
External Link: A hyperlink that is a reference or navigation element in a document or website to another document or to another website.
Google AdWords: Also known as AdWords, AdWords ads are displayed along with search results when someone searches Google using one of your keywords. Ads appear under ‘Sponsored links’ in the side column of a search page, and may also appear in additional positions above the free search results. You can choose from a variety of ad formats, including text, image, and video ads, and easily track your ad performance using the reports available in your account.
Google Analytics: A free service offered by Google that generates detailed statistics about the visitors to a website. The product is aimed at marketers as opposed to webmasters and technologists from which the industry of web analytics originally grew. It is the most widely used website statistics service.
Google Analytics Premium: An enterprise level, paid version of Google Analytics which among other things, provides more data, extra processing power and a dedicated support team. Currently, Google Analytics Premium costs $150,000 per year.
Google Personalized Search: A feature of Google Search and provided by Google. When a user is logged into a Google Account, all of their searches on Google Search are recorded into Google Web History. Then, when a user performs a search, the search results are not only based on the relevancy of each web page to the search term, but the service also takes into account what websites the user previously visited through search results to determine which search results to determine for future searches, to provide a more personalized experience. The feature only takes effect after the user has performed several searches, so that it can be calibrated to the user’s tastes.
Google Webmaster Tools: A no-charge web service by Google for webmasters. It allows webmasters to check indexing status and optimize visibility of their websites.
Grassroots Marketing: See Viral Marketing
Guerilla Marketing: See Viral Marketing
Impression: In online advertising via both CPC and CPM bidding strategies, an impression is a count of every instance an ad is shown, whether it is clicked or not.
Inbound/Back Link: Any link received by a web node (web page, directory, website, or top level domain) from another web node. The number and quality of inbound links to a website are the primary ranking factors used in Google’s ranking algorithm.
Index: Search engine indexing collects, parses, and stores data to facilitate fast and accurate information retrieval. Index design incorporates interdisciplinary concepts from linguistics, cognitive psychology, mathematics, informatics, physics, and computer science. An alternate name for the process in the context of search engines designed to find web pages on the Internet is Web indexing.
Infographic: Information graphics or infographics are graphic visual representations of information, data or knowledge. These graphics present complex information quickly and clearly, such as in signs, maps, journalism, technical writing, and education.
Internal Links: A hyperlink that is a reference or navigation element in a document or website to another section of the same document or to another document that may be on or part of the same website or domain of the internet.
Internet Protocol Address (IP Address): A numerical label assigned to each device (e.g., computer, printer) participating in a computer network that uses the Internet Protocol for communication. An IP address serves two principal functions: host or network interface identification and location addressing.
Key Performance Indicator (KPI): A type of performance measurement. KPIs are commonly used by an organization to evaluate its success or the success of a particular activity in which it is engaged. Sometimes success is defined in terms of making progress toward strategic goals, but often, success is simply the repeated achievement of some level of operational goal (contact form completion, newsletter signup, purchases, etc).
Keyword: Any term that an individual would use in order to find what they are looking for on the Internet. Keywords can consist of a word, phrase, or alphanumerical term.
Keyword Density: The percentage of times a keyword or phrase appears on a web page compared to the total number of words on the page. In the context of search engine optimization keyword density can be used as a factor in determining whether a web page is relevant to a specified keyword or keyword phrase.
Landing Page: Sometimes known as a lead capture page, a landing page is a single web page that appears in response to clicking on an online advertisement. The landing page will usually display directed sales copy that is a logical extension of the advertisement or link. Often times, landing pages are only accessible directly from clicking on an ad and are not navigable from the main website.
Lead Generation: Also knows as Lead Gen, it is a marketing tool used, particularly in internet marketing, to generate consumer interest or inquiry into products or services of a business. Leads can be generated for a variety of purposes – list building, e-newsletter list acquisition or for winning customers.
Link Bait: any content or feature, within a website, designed specifically to gain attention or encourage others to link to the website. The term often has a negative or dismissive connotation. The content for link baiting would be a text, image, audio or video clip and it interesting enough to catch the people’s attention.
Link Development: The act of obtaining inbound links to a website.
Link Juice: The amount of authority an outbound link from one website passes to another website based upon the strength of the outbound linking site in the eyes of a search engine.
Link Popularity: A raw count of how “popular” a page is based on the number of inbound links it has. It does not factor in link context or link quality, which are also important elements in how search engines make use of links to impact rankings.
Local Search: The organic results delivered by a search engine based upon the location of the user, the type of business being searched, or the search term itself. Local search results may include business ratings, reviews, maps and driving directions.
The Long Tail: First coined by Chris Anderson in an October 2004 Wired magazine article to describe the niche strategy of certain business such as Amazon.com or Netflix. In relation to search engine marketing (SEM) the Long Tail refers to the keyword phrases that are highly detailed and specific and may generate low volumes of searches and traffic, but add up to generate a majority of traffic for sites with deep content or product SKUs.
Marketing Automation: The name given to software platforms designed for marketing departments and organizations to automate repetitive tasks. Marketing departments, consultants and part-time marketing employees benefit by specifying criteria and outcomes for tasks and processes which are then interpreted, stored and executed by software, which increases efficiency and reduces human error. It was originally called email marketing automation.
Meta Search Engine: A search tool that sends user requests to several other search engines and/or databases and aggregates the results into a single list or displays them according to their source.
Meta Description Tag: Unlike the keywords attribute, the description attribute is supported by most major search engines, like Yahoo and Bing, while Google will fall back on this tag when information about the page itself is requested. The description attribute provides a concise explanation of a Web page’s content. This allows the Web page authors to give a more meaningful description for listings than might be displayed if the search engine was unable to automatically create its own description based on the page content.
Meta Elements: The HTML or XHTML <meta … > element used to provide structured metadata about a Web page. Multiple elements are often used on the same page: the element is the same, but its attributes are different. Meta elements can be used to specify page description, keywords and any other metadata not provided through the other head elements and attributes.
Meta Keywords Tag: The keywords attribute was popularized by search engines such as Infoseek and AltaVista in 1995, and its popularity quickly grew until it became one of the most commonly used meta elements. By late 1997, however, search engine providers realized that information stored in meta elements, especially the keywords attribute, was often unreliable and misleading, and at worst, used to draw users into spam sites.
Meta Robots Tag: Supported by several major search engines, the robots tag controls whether search engine spiders are allowed to index a page, or not, and whether they should follow links from a page, or not.
Meta Title Tags: Title tags are used to create the headline in the organic search results on most major search engines. The title tag is also displayed at the top of a users’ browser when they are on a webpage.
Microblogging: A broadcast medium in the form of blogging. A microblog differs from a traditional blog in that its content is typically smaller in both actual and aggregate file size. Microblogs allow users to exchange small elements of content such as short sentences, individual images, or video links.
Microsoft adCenter: adCenter ads are displayed along with search results when someone searches Bing or Yahoo using one of your keywords. Ads appear under ‘Ads’ in the side column of a search page, and may also appear in additional positions above the free search results. You can easily track your ad performance using the reports available in your account.
Mobile Marketing: Marketing on or with a mobile device, such as a cell phone using SMS Marketing, or an organization optimizing PPC advertisements for mobile devices.
Mobile Search: An evolving branch of information retrieval services that is centered around the convergence of mobile platforms and mobile phones and other mobile devices. Web search engine ability in a mobile form allows users to find mobile content on websites which are available to mobile devices on mobile networks. As this happens mobile content shows a media shift toward mobile multimedia. Simply put, mobile search is not just a spatial shift of PC web search to mobile equipment, but is witnessing more of treelike branching into specialized segments of mobile broadband and mobile content, both of which show a fast-paced evolution.
Multivariate Testing: A process by which more than one component of a website may be tested in a live environment. It can be thought of in simple terms as numerous A/B tests performed on one page at the same time. A/B tests are usually performed to determine the better of two content variations; multivariate testing can theoretically test the effectiveness of limitless combinations. The only limits on the number of combinations and the number of variables in a multivariate test are the amount of time it will take to get a statistically valid sample of visitors and computational power.
No Follow Link: Nofollow is a value that can be assigned to the rel attribute of an HTML element to instruct some search engines that a hyperlink should not influence the link target’s ranking in the search engine’s index. It is intended to reduce the effectiveness of certain types of search engine spam, thereby improving the quality of search engine results and preventing spamdexing from occurring.
Online Public Relations: See Search Engine Marketing Public Relations
Online Reputation Management (ORM): The practice of monitoring the Internet reputation of a person, brand or business, with the goal of suppressing negative mentions entirely, or pushing them lower on search engine results pages to decrease their visibility.
OpenSearch: A collection of technologies that allow publishing of search results in a format suitable for syndication and aggregation. It is a way for websites and search engines to publish search results in a standard and accessible format.
Organic Listings: Listings on search engine results pages that appear because of their relevance to the search terms, as opposed to their being advertisements. In contrast, non-organic search results may include pay per click advertising.
Outbound Links: see External Link
Pay-per-Call: Similar to pay per click, pay per call is a business model for ad listings in search engines and directories that allows publishers to charge local advertisers on a per-call basis for each lead (call) they generate (CPA). Advertiser pays publisher a commission for phone calls received from potential prospects as response to a specific publisher ad.
Pay-per-Click (PPC): See Cost-per-Click
Pay-per-lead (PPL)/Pay-per-Action (PPA): Advertiser pays publisher a commission for every visitor referred by the publisher to the advertiser (website) and performs a desired action, such as filling out a form, creating an account or signing up for a newsletter. This compensation model is very popular with online services from internet service providers, cell phone providers, banks (loans, mortgages, credit cards) and subscription services.
Paid Listings: See Pay-per-Click
Page Views: A request to load a single HTML file (‘page’) of an Internet site. On the World Wide Web a ‘page’ request would result from a web surfer clicking on a link on another ‘page’ pointing to the ‘page’ in question. This should be contrasted with a hit, which refers to a request for any file from a web server. There may therefore be many hits per ‘page’ view since an html ‘page’ can be made up of multiple files.
Paid Inclusion: A search engine marketing product where the search engine company charges fees related to inclusion of websites in their search index. Also known as sponsored listings, paid inclusion products are provided by most search engine companies, the most notable being Google.
Personalized Search: See Google Personalized Search
Rank/Position: The spot where a website appears in the organic search results. Generally speaking, sites in the top rank or position see much more organic traffic relative to lower ranked sites, with a dramatic drop-off after the first page (top ten listings).
Reciprocal Link: A mutual link between two objects, commonly between two websites to ensure mutual traffic. For example, Alice and Bob have websites. If Bob’s website links to Alice’s website, and Alice’s website links to Bob’s website, the websites are reciprocally linked. Reciprocal linking used to be effective from a search engine optimization perspective, but today provides little to no value to a site.
Redirect: Also called URL forwarding and the very similar technique domain redirection also called domain forwarding, are techniques on the World Wide Web for making a web page available under many URLs. There are various types of redirects including a 301 (permanently moved to a new URL) and 302 (temporarily moved to a new URL).
Referral Traffic: The traffic to a website that comes from other sites on the web.
Return-on-Advertising-Spend (ROAS): Represents the dollars earned per dollars spent on the corresponding advertising. To determine ROAS, divide revenue derived from the ad source by the cost of that ad source. Values less than one indicate that less revenue is generated than is spent on the advertising. A full cost/benefit analysis requires consideration of profit, instead of revenue, versus advertising spending.
Return-on-Investment (ROI): The ratio of money gained or lost (whether realized or unrealized) on an investment relative to the amount of money invested. The amount of money gained or lost may be referred to as interest, profit/loss, gain/loss, or net income/loss. The money invested may be referred to as the asset, capital, principal, or the cost basis of the investment. ROI is usually expressed as a percentage.
Robots.txt: The Robot Exclusion Standard, also known as the Robots Exclusion Protocol or robots.txt protocol, is a convention to prevent cooperating web crawlers and other web robots from accessing all or part of a website which is otherwise publicly viewable. Robots are often used by search engines to categorize and archive web sites, or by webmasters to proofread source code. The standard is different from, but can be used in conjunction with, Sitemaps, a robot inclusion standard for websites.
RSS Feeds: A family of web feed formats used to publish frequently updated works—such as blog entries, news headlines, audio, and video—in a standardized format. An RSS document (which is called a “feed”, “web feed”, or “channel”) includes full or summarized text, plus metadata such as publishing dates and authorship.
Schema.org: An initiative launched in June of 2011 by Bing, Google and Yahoo! to introduce the concept of the Semantic Web to websites. In November 2011 Yandex (largest search engine in Russia) joined the initiative. The operators of the world’s largest search engines propose to mark up website content as metadata about itself, using microdata, according to their schemas. Those schemas can be recognized by search engine spiders and other parsers, thus gaining access to the meaning of the sites. The initiative started with a small number of formats, but the long term goal is to support a wider range of schemas. The initiative also describes an extension mechanism for adding additional properties.
Search Engine: A web search engine is designed to search for information on the World Wide Web and FTP servers. The search results are generally presented in a list of results often referred to as SERPS, or “search engine results pages.” The information may consist of web pages, images, information and other types of files. Some search engines also mine data available in databases or open directories. Unlike web directories, which are maintained only by human editors, search engines also maintain real-time information by running an algorithm on a web crawler.
Search Engine Marketing (SEM): A form of Internet marketing that seeks to promote websites by increasing their visibility in search engine result pages (SERPs) through the use of paid placement, contextual advertising, and paid inclusion. Search engine optimization (SEO) “optimizes” website content to achieve a higher ranking in search results, for example, by incorporating specific keywords or links associated with the website. Depending on the context, SEM can be an umbrella term for various means of marketing a website including SEO, or it may contrast with SEO, focusing on just paid components (PPC).
Search Engine Marketing Public Relations (SEM PR): Using traditional PR methodologies to create online content, increase visibility and traffic via a hybrid of traditional PR strategies & facets of search engine marketing methodologies.
Search Engine Optimization (SEO): The process of improving the visibility of a website or a web page in search engines via the “natural” or un-paid (“organic” or “algorithmic”) search results. In general, the earlier (or higher ranked on the search results page), and more frequently a site appears in the search results list, the more visitors it will receive from the search engine’s users. SEO may target different kinds of search, including image search, local search, video search, academic search, news search and industry-specific vertical search engines.
Search Engine Positioning (SEP): See Rank/Position
Search Engine Results Page (SERP): The listing of web pages returned by a search engine in response to a keyword query. The results normally include a list of web pages with titles, a link to the page, and a short description showing where the Keywords have matched content within the page. A SERP may refer to a single page of links returned, or to the set of all links returned for a search query.
Search Engine Submission: How a webmaster submits a web site directly to a search engine. While Search Engine Submission is often seen as a way to promote a web site, it generally is not necessary because the major search engines like Google, Yahoo, and Bing use crawlers, bots, and spiders that eventually would find most web sites on the Internet all by themselves.
Search Personalization: See Personalized Search
Search Terms: See Keyword
Shopping Search/Feeds: See XML Feeds
Site Optimization: See Search Engine Optimization
Social Media: Refers to the use of web-based and mobile technologies to turn communication into an interactive dialogue. Andreas Kaplan and Michael Haenlein define social media as “a group of Internet-based applications that build on the ideological and technological foundations of Web 2.0, and that allow the creation and exchange of user-generated content.
Social Media Marketing (SMM): An addition to personal, small business, corporate, and non-profit organizations’ integrated marketing communications plans. The process of using social media as part of your integrated marketing plan.
Social Media Monitoring & Analysis: Tracking of various social media content such as blogs, wikis, micro-blogs, social networking sites, video/photo sharing websites, forums, message boards, and user-generated content in general as a way for marketers to determine the volume and sentiment around a brand or topic in social media. Can be directly related to Online Reputation Management.
Social Media Optimization (SMO): The methodization of social media activity with the intent of attracting unique visitors to website content. SMO is one of many online methods of website optimization.
Spamdexing: Also known as Search Spam, search engine spam or web spam, spamdexing is the deliberate manipulation of search engine indexes. It involves a number of methods, such as repeating unrelated phrases, to manipulate the relevance or prominence of resources indexed in a manner inconsistent with the purpose of the indexing system.[
Split Testing: see A/B Testing
Submission: See Search Engine Submission
Title Tag: See Meta Title Tag
Unique Visitor: Refers to a person who visits a Web site more than once within a specified period of time. Different from a site’s hits or page views, which are measured by the number of files that are requested from a site, unique visitors are measured according to their unique IP addresses. Unique visitors are counted only once no matter how many times they visit the site.
Universal Search: The process by which Google blends listings from various search properties (news, YouTube, images, local, book search engines, etc.) among those it gathers from crawling web pages.
Uniform Resource Locator (URL): A specific character string that constitutes a reference to an Internet resource.
Viral Marketing: Viral marketing, viral advertising, or marketing buzz are buzzwords referring to marketing techniques that use pre-existing social networks to produce increases in brand awareness or to achieve other marketing objectives (such as product sales) through self-replicating viral processes, analogous to the spread of viruses or computer viruses. It can be delivered by word of mouth or enhanced by the network effects of the Internet. Viral marketing may take the form of video clips, interactive Flash games, advergames, ebooks, brandable software, images, or text messages.
Virtual Engagement: Also known as Engagement Metrics, it is a metric to determine the level of affinity between a company and its customers
Visitor Session: What a visitor does when they are visiting a site comprises the session. The session ends when the visitor leaves the site, or after they are idle for 30 minutes or more.
Web 2.0: Web applications that facilitate participatory information sharing, interoperability, user-centered design, and collaboration on the World Wide Web. A Web 2.0 site allows users to interact and collaborate with each other in a social media dialogue as creators (prosumers) of user-generated content in a virtual community, in contrast to websites where users (consumers) are limited to the passive viewing of content that was created for them. Examples of Web 2.0 include social networking sites, blogs, wikis, video sharing sites, hosted services, web applications, mashups and folksonomies.
Webmaster Tools: Refers to either Google Webmaster Tools or Bing Webmaster Tools.
XML Feeds (Extensible Markup Language): A set of rules for encoding documents in machine-readable form. It is defined in the XML 1.0 Specification produced by the W3C, and several other related specifications, all gratis open standards. The design goals of XML emphasize simplicity, generality, and usability over the Internet. It is a textual data format with strong support via Unicode for the languages of the world. Although the design of XML focuses on documents, it is widely used for the representation of arbitrary data structures, for example in web services. Many application programming interfaces (APIs) have been developed that software developers use to process XML data, and several schema systems exist to aid in the definition of XML-based languages.